The creatures, known as anomalocaridids, were giant predators (ranging from 2 to possibly 6 feet in length) with soft-jointed bodies and toothy maws with spiny limbs in front to snag worms and other prey.

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Past research showed they dominated the seas during the early and middle Cambrian period 542 million to 501 million years ago, a span of time known for the “Cambrian Explosion” that saw the appearance of all the major animal groups and the establishment of complex ecosystems.

A normal length is actually about three feet, but this find is interesting I view of the fact that we are accustomed to thinking of Cambrian creatures as rather small. They also lasted much longer than expected.

File under: Bigger than expected, earlier than expected, around longer than expected, expect the unexpected.

8 Responses to Three foot killer shrimp of the Cambrian surprise scientists

Giant Sea Scorpion Discovered; Was Bigger Than a Man – Nov. 2007
Excerpt: The size of a large crocodile, the 390-million-year-old sea scorpion was the top predator of its day, slicing up fish and cannibalizing its own kind in coastal swamp waters, fossil experts say. Jaekelopterus rhenaniae measured some 8.2 feet (2.5 meters) long, scientists estimate, based on the length of its 18-inch (46-centimeter), spiked claw. The find shows that arthropods—animals such as insects, spiders, and crabs, which have hard external skeletons, jointed limbs, and segmented bodies—once grew much larger than previously thought, said paleobiologist Simon Braddy of the University of Bristol in the United Kingdom.

“This is an amazing discovery,” Braddy said.

“We have known for some time that the fossil record yields monster millipedes, supersized scorpions, colossal cockroaches, and jumbo dragonflies,” he added. “But we never realized, until now, just how big some of these ancient creepy-crawlies were.”http://news.nationalgeographic.....rpion.html

Bornagain77 at 4, “We have known for some time that the fossil record yields monster millipedes, supersized scorpions, colossal cockroaches, and jumbo dragonflies,” he added. “But we never realized, until now, just how big some of these ancient creepy-crawlies were.”

Fossils suggested these ancient marine predators grew to about 2 feet long. Prior studies also suggested they died out at the end of the Cambrian.

Moreover, these newly examined creatures date back to the period that followed the Cambrian, the early Ordovician, 488 million to 472 million years ago, meaning these predators lived for 30 million years longer than previously known.